提高废水资源化水平推进炼油企业节水减排

分析了当前石化行业水资源短缺的现状和加快污水回用进程、提高水资源综合利用水平的必要性和紧迫性，着重介绍了镇海炼化公司在提高水污染防治水平方面所取得的成效，以及在污水回用方面所做的探索性工作。     

流域累积效应及其评估中存在问题的探讨

阐述了累积效应、流域累积效应和累积效应评估的概念，并从技术、哲学和社会价值体系3方面着重论述了螺积效应评估存在的问题。通过对流域累积效应评估的研究及未来展望，提出了更加完善合理的流域生态管理思路。     

Particle-bound PAH content in ambient air

Ambient air samples from a traffic intersection, an urban site and a petrochemical-industrial site (PCI) were collected by using several dry deposition plates, two Microorifice uniform deposited impactors (MOUDIs), one Noll Rotary Impactor (NRI) and several PS-1 (General Metal Work) samplers from March 1994 to June 1995 in southern Taiwan, to characterize the atmospheric particle-bound PAH content of these three areas. Twenty-one individual polycyclic aromatic hydrocarbons (PAHs) were analyzed primarily by using a gas chromatograph/mass spectrometer (GC/MS). In general, the sub-micron particles have a higher PAH content. This is due to the fact that soot from combustion sources consists primarily of fine particles and has a high PAH content. In addition, a smaller particle has a higher specific surface area and therefore may contain more organic carbon, which allows for more PAH adsorption. For a particle size range between 0.31 and 3.2 microm, both Urban/Traffic and PCI/Traffic ratios of particle-bound total-PAH content have the lowest values, ranging from 0.25 to 0.28 (mean = 0.26) and from 0.07 to 0.13 (mean = 0.10), respectively. This indicates that, during the accumulation process, the PAH mass shifted from a particle phase to a gas phase, or the particles aggregated with lower PAH-content particles, resulting in a reduction in particle-bound PAH content. By using the particle size distribution data, the dry deposition model in this study can provide a good prediction for the PAH content of dry deposition materials. In general, lower molecular weight PAHs had a larger fraction of dry deposition flux contributed by the gas phase; for 2-ring PAH (50.4, 46.3 and 28.4%), 3-ring PAHs (15.2, 15.4 and 11.7%) and 4-ring PAHs (13.0, 3.60 and 5.01%) for the traffic intersection, urban and PCI sites, respectively. For higher molecular weight PAHs-5-ring, 6-ring and 7-ring PAHs-their cumulation fraction (F%) of dry deposition flux contributed by the gas phase was lower than 3.26%. At the traffic intersection, urban and PCI sites, the mass median diameter of dry deposition materials (MMD(F)) of individual PAHs was between 25.3 and 49.6 microm, between 27.6 and 43.9 microm, and between 19.1 and 41.9 microm, respectively. This is due to the fact that PAH dry-deposition primarily resulted from gravitational settling of the coarse particulates (> 10 microm).     

钢渣预处理含铬废水及其废渣与铬渣的固化

用钢渣对含铬废水进行预处理，探讨了钢渣粒度、用量、废水pH值和添加硫酸亚铁还原剂的影响。结果表明，经硫酸亚铁还原处理后再用钢渣处理比单纯用钢渣处理的效果明显提高，采用钢渣／总铬质量比为40的100目钢渣处理经硫酸亚铁还原后的含铬废水，总铬和Cr^6＋去除率分别达79％和84％，采用钢渣柱进行的两级淋滤实验进一步表明该方法可作为工业上含铬废水处理的预处理段。处理后的废钢渣同工业铬渣一起进行水泥固化，标准养护20d后固化体表面Cr^6＋浸出率、破碎至5mm粒径以下和酸雨淋溶下的浸出液Cr^6＋浓度均符合安全标准，可作为普通建材或进行填埋处置。     

Removal efficiencies of PCDDs/PCDFs by air pollution control devices in municipal solid waste incinerators

Removal efficiencies of polychlorinated dibenzo-p-dioxins/polychlorinated dibenzofurans (PCDDs/PCDFs) by air pollution control devices (APCDs) in the commercial-scale municipal solid waste (MSW) incinerators with a capacity of above 200 ton/day were evaluated. The removal efficiencies of PCDDs/PCDFs were up to 95% when the activated carbon (AC) was injected in front of electrostatic precipitator (EP). Spray dryer absorber/bag filter (SDA/BF) had high removal efficiency (99%)) of PCDDs/PCDFs when a mixture of lime and AC was sprayed into the SDA. When the AC was not added in scrubbing solution, the whole congeners of PCDDs/PCDFs were enriched in the wet scrubber (WS) with negative removal efficiencies of -25% to -5731%. Discharge of PCDDs/PCDFs was decreased with increasing the proportions of AC added in scrubbing solution. Selective catalytic reduction (SCR) system had the removal efficiencies of up to 93% during the test operation.     

Effects of nitrogen dioxide and its acid mist on reactive oxygen species production and antioxidant enzyme activity in Arabidopsis plants

Nitrogen dioxide (NO₂) is one of the most common and harmful air pollutants. To analyze the response of plants to NO₂ stress, we investigated the morphological change, reactive oxygen species (ROS) production and antioxidant enzyme activity in Arabidopsis thaliana (Col-0) exposed to 1.7, 4, 8.5, and 18.8 mg/m³ NO₂. The results indicate that NO₂ exposure affected plant growth and chlorophyll (Chl) content, and increased oxygen free radical (O₂⁻) production rate in Arabidopsis shoots. Furthermore, NO₂ elevated the levels of lipid peroxidation and protein oxidation, accompanied by the induction of antioxidant enzyme activities and change of ascorbate (AsA) and glutathione (GSH) contents. Following this, we mimicked nitric acid mist under experimental conditions, and confirmed the antioxidant mechanism of the plant to the stress. Our results imply that NO₂ and its acid mist caused pollution risk to plant systems. During the process, increased ROS acted as a signal to induce a defense response, and antioxidant status played an important role in plant protection against NO₂/nitric acid mist-caused oxidative damage.     

机动车尾气污染与防治措施研究

改善空气质量,减少机动车尾气对雾霾的贡献已是当务之急.防治机动车尾气污染,关键是国家应制定和完善相应的法律、法规、规章和标准,出台鼓励新能源机动车的研发、生产、销售的优惠政策.环保部门要把住机动车环保检测第一关,严格机动车环保绿色标志的发放,会同工商部门对油品实行日常监管,加强环保宣传、提高人们的环保意识.公安、环保联动执法,杜绝超标车上路,淘汰黄标车.政府相关部门要科学规划和绿化城市道路.     

管材对供水管网生物膜微生物种群多样性的影响

研究了3种管材(灰口铸铁管、镀锌管和不锈钢复合管)对管网生物膜微生物种群多样性的影响.采用R2A平板培养计数可培养细菌、荧光定量PCR计数细菌总数、流式细胞法确定活菌比例、扫描电镜观察生物膜形态,高通量测序研究管段生物膜微生物种群多样性.研究结果表明:灰口铸铁管可培养菌数和细菌总数都最高,其次是镀锌管,不锈钢复合管可培养菌数和细菌总数都最少,但活菌比例方面镀锌管活菌比例高于灰口铸铁管和不锈钢复合管.扫描电镜结果与可培养菌数及细菌总数结果一致,即灰口铸铁管细菌量最高,不同管材管壁生物膜细菌形态皆以球菌和杆菌为主,并无显著差异.微生物种群多样性结果显示:灰口铸铁管生物膜种群多样性最高,镀锌管生物膜种群多样性相对较为单一,不锈钢复合管生物膜种群多样性最低.饮用水管网生物膜种群以变形菌门为主,各管道变形菌门都高达90%以上,不同管材生物膜细菌群落组成有很大差异.本研究结果对今后饮用水供水管段材料的选取具有指导性意义.     

给水管网中污染物在管垢上的累积和释放

给水管网中,管垢是各种污染物的源和汇,但目前污染物在管垢中的累积释放特征尚缺乏系统研究.本文以实际的城市供水管网的球墨铸铁管和灰口铸铁管为对象,一方面采用扫描电镜(SEM)、能谱分析(EDS)、晶体衍射结构分析(XRD)等手段对其管垢进行表征,另一方面运用管段滞流反应器研究了三氯甲烷、铅、锰和锌等污染物滞流状态下在管垢上累积和释放特征.结果表明:同为铸铁管,使用一定年限后,管垢成分有所差异,灰口管管垢量较大,具有明显的锈蚀和管瘤出现,成分以二氧化硅、金属复合氧化物为主,而球墨管管垢量较小,以二氧化硅为主;随着初始浓度的提高,管垢对污染物的累积量逐步提高,对于三氯甲烷,其吸附量和释放量都非常低,而对于Pb、Mn和Zn 3种金属,管垢的吸附量远大于释放量,说明在实验条件下它们易累积不易释放,但水质条件的改变有可能引起大规模释放.研究结果对饮用水管网生物化学安全提出了更高的要求,为管网的饮用水安全保障提供了理论依据.